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Steve H. Faulkner and Philippa Jobling
Purpose: Cycling time trials (TTs) are characterized by riders’ adopting aerodynamic positions to lessen the impact of aerodynamic drag on velocity. The optimal performance requirements for TTs likely exist on a continuum of rider aerodynamics versus physiological optimization, yet there is little empirical evidence to inform riders and coaches. The aim of the present study was to investigate the relationship between aerodynamic optimization, energy expenditure, heat production, and performance. Methods: Eleven trained cyclists completed 5 submaximal exercise tests followed by a TT. Trials were completed at hip angles of 12° (more horizontal), 16°, 20°, 24° (more vertical), and their self-selected control position. Results: The largest decrease in power output at anaerobic threshold compared with control occurred at 12° (−16  W, P = .03; effect size [ES] = 0.8). There was a linear relationship between upper-body position and heat production (R2 = .414, P = .04) but no change in mean body temperature, suggesting that, as upper-body position and hip angle increase, convective and evaporative cooling also rise. The highest aerodynamic–physiological economy occurred at 12° (384  W·CdA−1·L−1·min−1, ES = 0.4), and the lowest occurred at 24° (338  W·CdA−1·L−1·min−1, ES = 0.7), versus control (367  W·CdA−1·L−1·min−1). Conclusion: These data suggest that the physiological cost of reducing hip angle is outweighed by the aerodynamic benefit and that riders should favor aerodynamic optimization for shorter TT events. The impact on thermoregulation and performance in the field requires further investigation.
Brady M. Smith, David O. Draper, Robert D. Hyldahl and Justin H. Rigby
Context: Low current intensity iontophoresis treatments have increased skin perfusion over 700% from baseline potentially altering drug clearance from or diffusion to the targeted area. Objective: To determine the effects of a preceding 10-minute ice massage on subcutaneous dexamethasone sodium phosphate (Dex-P) concentration and skin perfusion during and after a 4-mA iontophoresis treatment. Design: Controlled laboratory study. Setting: Research laboratory. Patients or Other Participants: Twenty-four participants (male = 12, female = 12; age = 25.6 [4.5] y, height = 173.9 [8.51] cm, mass = 76.11 [16.84] kg). Intervention(s): Participants were randomly assigned into 2 groups: (1) pretreatment 10-minute ice massage and (2) no pretreatment ice massage. Treatment consisted of an 80-mA·minute (4 mA, 20 min) Dex-P iontophoresis treatment. Microdialysis probes (3 mm deep in the forearm) were used to assess Dex-P, dexamethasone (Dex), and its metabolite (Dex-Met) concentrations. Skin perfusion was measured using laser Doppler flowmetry. Main Outcome Measure(s): Microdialysis samples were collected at baseline, at conclusion of treatment, and every 20 minutes posttreatment for 60 minutes. Samples were analyzed to determine Dex-Total (Dex-Total = Dex-P + Dex + Dex-Met). Skin perfusion was calculated as a percentage change from baseline. A mixed-design analysis of variance was used to determine Dex-Total and skin perfusion difference between groups overtime. Results: There was no difference between groups (P = .476), but [Dex-Total] significantly increased over the course of the iontophoresis and posttreatment time (P < .001). Dex-P was measured in 18 of 24 participants with a mean concentration of 0.67 (1.09) μg/mL. Skin perfusion was significantly greater in the no ice treatment group (P = .002). Peak skin perfusion reached 27.74% (47.49%) and 117.39% (103.45%) from baseline for the ice and no ice groups, respectively. Conclusions: Ice massage prior to iontophoresis does not alter the tissue [Dex-Total] even with less skin perfusion.
Derrick D. Brown, Jurjen Bosga and Ruud G.J. Meulenbroek
This study investigated effects of mirror and metronome use on spontaneous upper body movements by 10 preprofessional dancers in a motor task in which maximally diverse upper body movement patterns were targeted. Hand and trunk accelerations were digitally recorded utilizing accelerometers and analyzed using polar frequency distributions of the realized acceleration directions and sample entropy of the acceleration time. Acceleration directions were more variably used by the arms than by the torso, particularly so when participants monitored their performance via a mirror. Metronome use hardly affected the predictability of the acceleration time series. The findings underscore the intrinsic limitations that people experience when being asked to move randomly and reveal moderate effects of visual and acoustic constraints on doing so in dance.
Fábio Carlos Lucas de Oliveira, Amanda L. Ager and Jean-Sébastien Roy
Context: Recreational overhead athletes are exposed to high overload, which increases the risk of shoulder injuries. Reduction of the acromiohumeral distance (AHD) is often associated with rotator cuff–related shoulder pain (RCRSP) among the general population. However, the AHD of symptomatic shoulders of recreational athletes has not yet been compared with their asymptomatic shoulders. Objective: To compare the AHD of a symptomatic to asymptomatic shoulder at rest (0°) and 60° abduction. To establish the relationship between AHD, pain, and functional limitations of recreational athletes with RCRSP. Design: Cross-sectional study. Setting: University laboratory. Participants: A total of 45 recreational overhead athletes with RCRSP were examined. Main Outcome Measures: The AHD was measured by ultrasonography at 0° and 60° abduction (angles). Shoulder pain was assessed using a numeric pain scale, whereas functional limitations were assessed using the The Disabilities of the Arm, Shoulder, and Hand questionnaire. Differences in the between-shoulders condition (symptomatic and asymptomatic) were determined using 2-way analysis of variance for repeated measures. A Pearson correlation established the relationship between AHD, pain, and functional limitations. Results: No angles × shoulder condition interactions (P = .776) nor shoulder condition effects (P = .087) were detected, suggesting no significant differences (P > .05) between asymptomatic and symptomatic shoulders in the AHD at 0° or 60°. The AHD at 60° reduced significantly compared with 0° (3.05 [1.36] mm [2.77–3.33], angle effects: P < .001). The AHD at 0° and 60° was not correlated with pain or functional limitations (−.205 ≤ r ≤ .210, .167 ≤ P ≤ .585). Conclusions: The AHD of recreational athletes is not decreased in symptomatic shoulders compared with asymptomatic shoulders. Reduction of the AHD in symptomatic shoulders is not associated with an increase in pain or functional limitations of recreational athletes with RCRSP.
Naoya Takei, Katsuyuki Kakinoki, Olivier Girard and Hideo Hatta
Background: Training in hypoxia versus normoxia often induces larger physiological adaptations, while this does not always translate into additional performance benefits. A possible explanation is a reduced oxygen flux, negatively affecting training intensity and/or volume (decreasing training stimulus). Repeated Wingates (RW) in normoxia is an efficient training strategy for improving both physiological parameters and exercise capacity. However, it remains unclear whether the addition of hypoxia has a detrimental effect on RW performance. Purpose: To test the hypothesis that acute moderate hypoxia exposure has no detrimental effect on RW, while both metabolic and perceptual responses would be slightly higher. Methods: On separate days, 7 male university sprinters performed 3 × 30-s Wingate efforts with 4.5-min passive recovery in either hypoxia (FiO2: 0.145) or normoxia (FiO2: 0.209). Arterial oxygen saturation was assessed before the first Wingate effort, while blood lactate concentration and ratings of perceived exertion were measured after each bout. Results: Mean (P = .92) and peak (P = .63) power outputs, total work (P = .98), and the percentage decrement score (P = .25) were similar between conditions. Arterial oxygen saturation was significantly lower in hypoxia versus normoxia (92.0% [2.8%] vs 98.1% [0.4%], P < .01), whereas blood lactate concentration (P = .78) and ratings of perceived exertion (P = .51) did not differ between conditions. Conclusion: In sprinters, acute exposure to moderate hypoxia had no detrimental effect on RW performance and associated metabolic and perceptual responses.
Evidence supporting exercise as a medicine in the prevention and management of chronic disease is indisputable. Created in 2007, Exercise is Medicine® (EIM) aims to make physical activity assessment and promotion a standard in clinical care, connecting health care professionals with qualified exercise professionals to provide evidence-based physical activity resources and programs to everyone of all abilities. Opportunities exist for exercise professionals in several areas within EIM, including exercise referral and prescription, EIM on Campus, and physical activity and EIM education. Connections between EIM and kinesiology and the need for exercise professionals to contribute to the EIM evidence are discussed.
Michelle Hamilton, Karen Meaney and Melissa Martinez
Promoting the success of all students is one of four institutional goals at Texas State University. Retention and graduation rates provide information regarding the academic progress and success of specific student cohorts. To gain a deeper insight into student success within the undergraduate kinesiology/exercise and sports science program at Texas State University, an equity audit was conducted during the fall 2019 academic semester. An equity audit provides a lens to critically examine institutional data to identify inequities in academic programs and student achievement based on specific variables, such as gender, age, race, and socioeconomic status. This article provides a model for conducting an equity audit in kinesiology/exercise and sports science programs, reports the findings, and highlights strategic actions implemented to combat inequities in student success.
Helene Pedersen, Atle Hole Saeterbakken, Markus Vagle, Marius Steiro Fimland and Vidar Andersen
Purpose: The Nordic hamstring exercise (NHE) has been shown to considerably reduce hamstring injuries among soccer players. However, as the load in the NHE is the person’s own bodyweight, it is a very heavy exercise and difficult to individualize. The flywheel inertial leg curl (FLC) could be an alternative since the eccentric overload is based on the amount of work produced in the concentric movement. Therefore, the primary aim of this study was to compare the activation in the hamstrings at long muscle lengths in the NHE and the FLC in amateur soccer players. Methods: Fifteen male amateur soccer players performed 5 repetitions in each exercise in a randomized and counterbalanced order. The concentric and eccentric movements were divided into lower and upper phases. Surface EMG was measured distally, proximally, and in the middle, at both muscles. Results: In the lower phase in the eccentric movement, there were no significant differences between the 2 exercises (P = .101–.826). In the lower concentric movement, the FLC led to higher activation in all parts of both the biceps femoris (31%–52%, P < .001) and the semitendinosus (20%–35%, P = .001–.023). Conclusion: Both exercises activated the hamstrings similarly at long muscle lengths during eccentric contractions (Nordic hamstring, nonsignificantly higher). However, when performing concentric contractions, the FLC induced higher activations. Therefore, the FLC could be a useful alternative to the NHE and particularly suitable for weaker athletes before progressing to NHE.
Jinhui Li, Chen Li, Bing Xun Chia, Xinran Chen, Tan Phat Pham and Yin-Leng Theng
This study examined how different types of social interaction and competitive information in exergaming affect older adults’ motivation and attitude toward playing exergames. A 2 (time: pre- vs. posttest) × 3 (social interaction: play alone vs. play with peer vs. play with youth) × 2 (competition: competition informed vs. noncompetition informed) mixed experiment was conducted with 319 Singaporean older adults over 6 weeks through a three-way analysis of variance. Social interaction was found to significantly affect the changes of extrinsic motivation over time, while competitive information affected intrinsic motivation significantly. The results showed significant three-way interaction effects between time, social interaction, and competitive information on older adults’ extrinsic and intrinsic motivations. The changes of attitude over time were not affected by either social interaction or competitive information. The findings contribute to aging research and advance the knowledge of potential factors that promote the effective implementation of exergames for community older adults.